Na~I/Cu~(I-II) heterometallic cages interconnected by unusual linear 2-coordinateOCN-Cu(I)-NCO links: synthesis, structural, magnetostructural correlationand computational studiest

摘要

A new Na~I /Cu~(I-II)heterometallic coordination complex [Cu_2L_2Na(NCO)_2Cu]_n (1) with an unusualarchitecture has been synthesised. In 1 cyclic Na-O-Cu-O-Cu cages constructed by the tetradentateN20, donor Schiff base ligand(H_2L)= N,N' -bis(2-hydroxyacetophenone)propylenediimine) areinterconnected to each other by a rare singly end-to-end bridged OCN-Cu(I)-NCO link generating 1Dchain. The complex has been characterised by elemental, spectral and structural analysis. The cyclicvoltammogram of 1 has been compared with the analogous complexes. Cryomagnetic susceptibilitystudies indicate the copper(II) centers in the cyclic Na-O-Cu-O-Cu cages are antiferromagneticallycoupled with J = -13.8 cm~(-1). Complex 1 is a new addition to a class of rare singlyend-to-endcyanatobridged copper(I) species and interestingly the copper ions involved in OCN-Cu(I)-NCO links possess alinear 2-coordinate geometry. Density functional theory calculations have been carried out to gainadditional insights into the metal and ligand orbitals participating in this unusual structure.